Method for manufacturing slide fasteners



23, 1949.. van- METHOD FOR MANUFACTURING SLIDE FASTENERS 6 SheetsSheet 1 Original Filed March 26, 1942 INVENTOR MflUE/CE 1/0/77 Original Filed Marc VOITY METHOD FOR MANUFACTURING SLIDE FASTENERS 6 Sheets-Sh g l NTOR F mu/e/ 1 0/ W BY a z W ORNEY a. 1;? flfl. M. vomr METHOD FOR MANUFACTURING SLIDE FASTENERS 6 Sheets-Sheet 3 Nun Original Filed March 26. 1942 INVENTOR M4UE/CE VO/ Ty ATTORNEY Aug. 23, 1949. M. VOlTY METHOD FOR MANUFACTURING SLIDE FASTENERS 6 Sheets-Sheet 4 Original Filed March 26, 1942 mow INVENTOR MIQUP/CE VO/ 7y Aug, 23,. 1949.. M. VOITY 2,480,061

METHOD FOR MANUFACTURING SLIDE FASTENERS Original Filed March 26, 1942 6 Sheets-Sheet 5 R Y .7 5 W m v N IF- A m 7 3a W Y w \mwv. m NR 4 am 2: Q2 0 L M A am mm wt M o l +5 NM M i QQN v u an A Eq 9 v N8 W .i 2 +2 W inmunu h Ni r \H vem I won I N w A. H 09w gm w mww g g 3m gm H NNN 23, 1949. M. VOlTY, 2,480,061

METHOD FOR MANUFACTURING SLIDE FASTENERS Original Filed March 26, 1942 a Sheets-Sheet s INVENTOR M4UPIC VO/TY Patented Aug. 23, 1949 Maurice Voity, New York, N. Y., asslgnor tosernl Slide Fasteners, York Inc., a corporation of New Original application March 26, 1942, Serial-No.

436,279. Divided and thisapnlleaflonll'arch 18, 1946, Serial No. 655,166-

This invention relates to slide fasteners. and

more particularly to a method for manufacturing the same, wherein long strips of integrally connected embryonic slide fastener elements are employed.

.One of the objects of my invention is to provide an improved process for successively severing individual elements from a strip of embryonic integrally connected elements and clamping said individual elements on a tape.

1 Claim. (Cl-153-4) Fig. 11 is a sectional view of the apparatustaken along the line ll-ll of Fig. 9;

12,and"13 are details. respectively, of the clamping mechanism and shearing anvil;

Fig. 14 is a sectional viewtak'en along the line l4'l4 of Fig. 11 and is explanatory of the tape v tensioning shoes;

Other objects of thisinvention will in part obvious and in part hereinafter pointed out.

The invention accordingly consists inthe features of construction, combinations of elements, and arrangement of parts which will be exemplified in the construction hereinafter described, and of which the scope of application will be indicated in the claim.

Certain features of the invention shown and described, but not claimed herein, are shown, described and claimed in my copending applications for Method and apparatus for manufacturing slide fasteners, Serial No. 363,805, filed November 1, 1940 (now U. S. Letters Patent No. 2,396,727) and Apparatus for manufacturing slide fasteners, Serial No. 436,279, filed March 26, 1942 (now U. S. Letters Patent No. 2,396,933), of which the.

present application is a division, and in my copending application for Apparatus for manufacturing slide fasteneraserial' No. 655,165, filed March 18, 1946 (now U. S. Letters Patent No. 2,473,623). 1

In the accompanying drawings, in which is shown one of the various possible embodiments of this invention,-

Figs. 1, 2 and 3 are top, side and bottom views, respectively, of a strip of embryonic integrally connected slide fastener elements formed in ac cordance with my invention;

Fig. 4 is a sectional view of said strip taken along the line 4-4 of Fig. 2;

Fig. 5 is a side view of a part of a completed slider string;

Fig. 6 is an enlarged perspective view of an individual slide fastener element separated from the formed strip but before it is clamped on a tape;

Figs. 7, 8 and 9 are side, end and plan views, respectively, of a severing and clamping apparatus embodying my invention;

Fig. 10 is a sectional view taken along the line Ill-40 of Fig. 9, and illustrating the mechanism employed to intermittently stop the feed of the formed strip in order to provide a space between groups of slider elements clamped on a tape;

Fig. is an enlarged view taken along the line l5-l5 of Fig. 9 showing a step during the operation of severing an. embryonic slide fastener element from the formed strip;

Fig. 16 is a sectional viewtaken along the line l6l6 of Fig.15; and

Figs. l'land 18 are views similarfto Figs. 15 and 16 but showing a further step.

Referring now to'the drawings and more particularlyto Figs. 1 through 4, I have shown a strip S of integrally connected slide fastener elements 20. Said strip may be fabricated on any suitable forming apparatus, such as for example that shown and described in my copending application, Serial No. 363,805. Said elements 20 are all faced in the same direction in the strip S (see Figs. 1-6) and each element 20 comprises a head 22 having the usual locking projection 24 and underlying socket 26. The projection 24 is provided with front. side and rear sloped guiding surfaces 28, 30 and 32 joined by concavely rounded corners/34 and abrupt edges 36. Said projections 24 rise from between a pair of parallel co-planar flats 38 and 48, which are joined by slopes 42 to the upper surface 44 of the embryonic jaws 46.

It will be noted that the lowest point 48 on the rear guiding surface 32 is disposed below the jaw surface 44, thus enabling the elements 20 to clear each other more easily in the interlocking operation.

The embryonic jaws 46 comprise a pair 01' spread legs 50, which are cut from the flats 38 and 40 along the dotted lines indicated in Fig. 1, in a manner hereinafter to be described. Each of the legs 50 projects angularly from its associated head 22 and includes an inner portion 52 (Fig. l) which lies outside of and immediately adjacent the locking projection 24 on the next following slider element 20; an intermediate portion 54 which lies outside of and immediately adjacent a flat portion 56 of the locking projection on the next following slider element 20; and an outer portion 58 which comprises one of th serrations forming an edge of the strip S.

The strip S is fed from a bobbin on which it is wound after fabrication into a high speed stringer assembling machine 60 (Figs. 7, 8, 9 and 11) embodying my invention, which machine successively cuts embryonic. slide fastener elements 20 from the strip and attaches them in. properly spaced relationship upon the slider tape T. The machine 80 is mounted on a bedplate 82 and the several moving parts thereof are actuated by a single drive shaft 84 which is disposed transversely of the direction of feed of the strip. The drive shaft may be actuated in any suitable fashion, as by means of a pulley 88 which is connected by a belt (not shown) to the drive pulley of an electric motor (not shown). A hand wheel 88 may also be employed to turn the shaft over by hand when the machine is being adjusted.

The strip S is advanced during the interval between the cuttin and clamping of a. slide fastener element 20 by a feed dog 10 set in a shaft 12 which is rotatably mounted in a feed block 14. One end of said shaft 12, which projects beyond a side of the block 14, has an arm 18 fixed thereto. A Spring 18 encircling the shaft 12 is anchored at one end thereof by a screw 80 threaded into an aperture in the block 14, the other end thereof passing through a hole 82 in the arm 18. In this manner the feed dog 10 is constantly urged in a counterclockwise direction, as viewed from Fig. 11, so that when the same is moved towards the clamping and severing portion of the machine 80, said feed dog will press against the rear surface 32 of an embryonic slide fastener element 20 to moved backwardly, the lower end thereof will ride over the locking projection 24 of an embryonic element 20 and come to rest immediately above the lowest point 42 on the said rear surface 32 ready to again advance the strips.

In order to move the feed dog 10 in the manner thus described, the block 14 is attached in any suitable manner to a feed lever 84, which oscillates about a pivot 88 and is provided with a slit 88 (Figs. 9 and 10) and coaxial bore 80. A shaft 92 is held in the bore 90 by means of a pair of screws 94 which freely pass through apertures 98 disposed on one side of the slit 88. Said screws are received in tapped holes 98 disposed'on the other side of said slit. It is thus seen that when the screws 94 are tightened so that their heads press against a side wall of the feed lever 84, the portions of said lever disposed on either side of the slit 88 will be sprung toward each other to grip the shaft 92 immovably therebetween.

The end of the shaft 82 projecting from the feed lever 84 has a circular cam follower I mounted to freely rotate thereon. Said cam follower rides upon the surface of a side-face cam I02 mounted on the drive shaft 84 for rotation therewith. Said cam I02 has only a single low point I04, the balance of the cam surface being otherwise of uniform height, so that the feed dog is actuated only once, for a very short period of advance the strip S. When the feed dog 10 is r time, during a single cycle of operation of the machine 80.

In order to cause the cam follower I00 to constantly engage the cam I02, 9. spring I08 may be held under compression between an arm portion I08 of the feed lever 84 and the enlarged head I I0 of a threaded rod II2 which is adjustably received in a tapped-hole I I4 of a casting I'I8 mounted on the bedplate 82. The compression under which the spring I08 is maintained may be varied by rotatin the rod II2 by means of a slot II8 formed at the free end thereof, and a lock nut I20 may be employed to hold the rod H2 in any adjusted position. Also, in order to prevent the spring I08 fromslipping. a nub I22 4 may be formed on the enlarged .head 0 of the rod H2 and a similar aligned nub I24 provided on a disc I26 which is attached to the arm portion I08 by means of a pin I 28 frictionally received in an aperture I therein.

To aid in guiding the strip through the machine 80, the under surface of the block 14 may be channeled to provide a passageway I82.

A check dog I34 in alignment with the feed dog 10 serves to prevent the strip S from being pulled back during retrograde movement of the feed dog 10. Said check dog I34 is set into a slot in a shaft I38 rotatably carried in a check block I38 fixed to the bedplate 82. A pull spring I40 engages an arm I42 mounted on an end of the shaft I36 projecting beyond one side of the block I38, the other end of the spring I40 being anchored to a post I44 set in the bedplate 62.

By this construction the tip of the check dog I34 will be raised upwardly by the locking projection 24 of an embryonic slide fastener element 20 when the strip S is advanced, thus allowing the head 22 to freely pass thereunder. However, as soon as as one of the heads has passed beyond the check dog I34, the latter will spring back to lie against the rear surface 32 of the head and thusprevent a retrograde movement thereof. The forward end of the block I88 may also have a channel I48 cut on the bottom surface thereof in alignment with the channel I32 in the feed block 14 to aid in further guiding the strip.

After the strip S passes the check dog I34, it is introduced into the guide channel I48 cut in the under surface of a stripper I50 (Figs. 11 and 12) attached to bedplate 82. A finger I52 protrudes from the forward surface of the stripper I50 to prevent the strip S from bein deformed during retraction of the severing die. It will be noted that the top surface of the channel I48 gradually slopes upwardly (as best shown in Fig; 11, where the slope is exaggerated), so that the forward end of the channel is elevated over the rear end of the channel a distance, slightly greater than the depth of the socket 28 in the embryonic slide fastener element. The forward end of the strip S may thus be fed over a positioning nub, hereinafter mentioned, on the shearing anvil. The under surface of the finger I52 isalso disposed at the higher level of the forward end of the channel I48.

Underlying the finger I82 and a portion of the forward end of the channel I48 is a floating pad I54 which is received in a sliding fit in a recess I58 in a two-piece jacket I58 doweled to the bedplate 82. The rear end of the pad I54 has a pro- Jecting ledge I80 which lies in a short cavity I82. Said ledge is provided on its opposite longitudinal sides with serrations similar in size and shape to the serrated edges of the strip S to cooperate with a pair of reciprocating serrated pilots I84 for accurately locating and rigidly holding the forward end of the strip S prior to and during shearing and clamping. The lower edge I88 of the pilot may be raked to facilitate registry of the strip. The forward face of the pad I54 is channeled as at I88 (Fig. 13) to snugly fit around a portion I10 of a shearing anvil I12 having a sectional contour corresponding to the outline of the head 22 of a slide fastener element. The pad I 54 is urged upwardly against stops on the jacket I58 by a rod I14 attached to a plunger I18 sliding in a bore I10 in the bedplate 82, anda spring I 80 is disposed in the said bore I18 beneath the plunger.

The cutting of the foremost embryonic slider fastener element 20 on the strips is performed by a reciprocating punch I82 having a thin severing edge I84 shaped similarly to the anvil I10. The lower surface of the punch I82 is spaced slightly above the lower surface of the pilots I64.

The shearing anvil I12 is suitably held rigidly in a slot which runs from top to bottom of the jacket I58 and faces the recess I56, thus allowing the forward portion I to project there-into, in the manner above described. A deep vertical slot I86 is formed along the entire length of the anvil I12 and is enlarged at its forward end into a circular aperture I88 positioned in proper relationship to the projecting portion I10 to receive and thereby accurately locate the head of the tape T with respect to the slide fastener elements. A small nub I90 on the upper face of the portion I10 is shaped so as to be snugly received in a socket 26 of a slider element 20. The rear portion of the punch I82 may be relieved as indicated at I92, since it is not necessary to conform the lower face of said plate to the contour of the upper face of the strip.

It is thus seen that when the strip S is advanced one step by the feed dog 10, the forward edge of the foremost embryonic slide fastener element 20 will encounter the sloped forward surface I94 of the positioning nub I90, to cause the front part of the strip S to ride upwardly into engagement with the upper surface of the channel I48. 'I'hereupon, said foremost element will clear the nub I90. The strip will then drop down with said foremost edge abutting the tape bead, the jaws 46 straddling the tape and the foremost socket 26 being fitted on the positioning nub I90. The pilots and punch I64 and I82 next simultaneously move downward to accurately position and hold the strip S and immediately thereafter cut off said foremost element 20. During the shearing operation, the pad I54 will be forced downwardly by the shearing plate I82, as indicated in Figs. and 17, leaving the severed element remaining on the anvil I12. I have found that by thus positioning the element to be severed on a stationary anvil during the shearing and allowing the strip to be moved with respect thereto, a high degree of accuracy is obtained in the spacing of the severed elements along the tape. When the punch is retracted, the pad I54 will move upwardly until its top surface is flush with the top surface of the anvil I12, to allow the next'forward feeding movement of the strip. Also the upward movement of the pad I54 strips the jaws 46 of the next embryonic element 20 from the anyilportion I10.

In order to provide for reciprocation of the pilots and punches i 64 and I82, the latter are clamped to a head I96 guided in vertical slideways I98 provided in a standard 200 mounted on the bedplate 82 over the stripper I50. The head I96 is intermittently forced in a downward direction against the action of a compression spring 202 by a screw 204 (Fig. 8) adjustably carried on the driving end 206 of a bell crank lever 208. Said screw abuts, for this purpose, a hardened plate 2I0 carried by the head I96. The other end of the lever 208 is provided with a pair of rollers 2I2, which ride on cams 2I4 rotating with the drive shaft 64. The lever 208 is journalled on a shaft 2I6 supported by posts 2I8.

The slider elements 20 are clamped to the tape T by a pair of coacting clamping jaws 220 rigidly attached to the ends of bell crank levers 222 and 224 pivoted about a pin 228. The levers 222 and 224 are actuated by a pair of rollers 228 and 230 riding in a pair of symmetrical oppositely acting channel cams 232 and 234, which are mounted on the drive shaft 84 in proper angular relationship to the other operating cams.

It should be particularly noted that the cams 232 and 234 are so arranged that the jaws 220 begin to exert a clamping action upon the spread laws 46 of the foremost slider element 20 immediately before the shearing is completed, as indicated in Figs. 15 and 16, where the clamping has just begun, so that the position of an element is always controlled.

Attention is also directed to the formation of the jaws 46 after clamping is completed (Fig. 18). The outer edge 236 of the jaw, which previously comprised one of the inclined edges of the serrated strip S, is disposed in registration with the outer edge of the flat 56 on the head 22, and the forward edge 238 which previously comprised the other inclined edge is disposed perpendicularly to the said outer edge 238, thus providing a square edge and a comparatively large surface for the slider ways to engage.

I provide the following mechanism for supporting the tape under tension during clamping and to advance the same intermittently between each clamping operation:

Journalled in a bearing 240 supported on the bedplate 62 is a shaft 242 which has keyed at one end a knurled tape drum 244 having an annular recess 246 in which the slider elements 20, after assembly on the tape, are received. A smooth-faced shoe 248 pivotally mounted at the lower end of a rod 259 is resiliently pressed against the tape T by a compression spring 252 to ensure a good frictional contact of the tape with the drum 244. Adjustment of the shoe pressure may be effected by means of a nut 254 and lock nut 256 threaded on the upper end of the rod 250 and abutting a cammed ring 258 nesting against the correspondingly cammed end 260 of a rod bracket 262. Shoe pressure may be wholly released while threading the tape by turning the ring 258 to disalign its cammed surface with that of rod bracket end 260.

The tape drum 244 is rotated by a ratchet wheel 264 intermittently actuated by a feed pawl 266 pivotally mounted on the upper end of an oscillating bell crank lever 268 journalled about the drum shaft 242. A spring 210 maintains the pawl 266 in constant engagement with the ratchet wheel 264. The lever 268 is angularly reciprocated by a link 212 pivoted to said lever and strapped at its other end around an eccentric 214 rotating with the drive shaft 64. A check pawl 218 is pivotally mounted on a stationary bracket 218 and is maintained in engagement with the ratchet wheel 264 by a spring 280.

Due to the high speed of the machine 60, I have found it desirable to provide means to prevent overdrive of the ratchet wheel 264 and tape drum 244 beyond the effective operating position of the check pawl 216. Such means preferably comprises a brake drum 282 integrally formed with the tape drum 244 and having a suitably lined brake 284 disposed thereabout. The ends of the brake are joined by a split bracket 286 having a pair of aligned apertures 288 in which are provided a tightening bolt 290 and nut 292. A spring 294 may encircle a projecting portion of the bolt shank. A pin 296 holds the bracket 286 to a stationary portion of the machine 60. Thus, by turning the bolt 290 to resiliently spring togetherv the spaced legs of the bracket 286, the proper amount of frictional drag may be applied to the shaft 242, which allow said shaft to be intermittently advanced under the positive driving action of the feed pawl 266, but will prevent any overdrive. By the use of this brake the minimum of tension may be applied to thetape, in the manner hereinafter described, to keep the tape taut and so prevent stretching of the tape during clamping, which has heretofore resulted in uncontrolled varying of stringer lengths.

Attention is directed to the slight inclination of the shaft 242 which causes the element which has been last fastened to the tape to clear the shearing plate I82 after it has been advanced one step, as clearly shown in Figs. 16 and 17, and to the alignment of the web of the tape with the strip S for its unsupported length 'between the anvil I 12 and tape drum 244. Both these features contribute to highly accurate spacing between the slider elements.

The tape, after it leaves the tape drum 24 4, is guided through a chute 238 into a container (not shown). The tape is fed from a spool (not shown) to the machine 50 through formed tensioning shoes 330 and 332 (Fig. 14), one of which, 330, is secured to the under surface of the bedplate 82. The other. shoe 382 is screwed to one end of a lever 334 pivoted to the bedplate 62 and is resiliently urged against the shoe 380 by a spring 386 caught to the lever 304. The spring is maintained under adjustable tension by a threaded rod 308 having a slotted portion nonrotatably engaging a pin 3| in a bracket 3|2 fixed-to the bedplate 62- A knurled handle 3, which threadedly engages the rod 308 and abuts the bracket 3l2, is provided to vary the tape tension.

I also provide means for varying the number of slide fastener elements contained in one group and the spacing between such groups. Such means may comprise a suitable counting mechanism 3l6 actuated by the drive shaft 64 which operates an electric switch 3| 8 connected in series with a source of electric power (not shown) and a solenoid 320 illustrated in energized position in, Fig. 10. The solenoid has an internally disposed core plunger 322 which is adapted to actuate a feed dog stop finger 324 through a linkage system, including a straight link 326 and an angled link 328. The system is normally maintained in inoperative position by a spring 330 tensioned belating feed lever 84 and feed dog It. However, as soon as the switch 3|! is closed by the counter M6, the solenoid 323 will be energized and urge the pin 324 upwardly. If at this time the plate tion of the lever 84 will be stopped. It will be noted that when the pin 324 is in the above locking position and the cam follower I80 is riding on the dwell of the side-face cam I02, the pin fiat 336 will be clear of the plate 340 by a few thousandths of an inch, thus allowing saidm to be retracted by the spring 333 upon de-energization of the solenoid 323 when the switch 3 l8 opens.

It will thus be seen that there is provided an apparatus and method for making slide fasteners in which the several objects of this invention are achieved. and which is well adapted to meet the conditions of practical use.

-As various possible embodiments might be made of the above invention, and as various changes might be made in the embodiments above set forth, it is to be understood that all matter herein set forth or shown in the accompanying drawings is to be interpreted as illustrative and not in a limiting sense.

Having thus described my invention, I claim as new and desire to secure by Letters Patent:

In a method of assembling slide fastener elements on a tape, that improvement which comprises intermittently feeding a continuous strip having integral embryonic slide fastener elements uniformly formed and positioned thereon with their jaws facing forwardly, intermittently feeding a tape, successively severing the foremost element from the strip, attaching said elements to the tape, fixedly and undeviatingly maintaining tween the pivot 332 interconnecting the links 328 and 328 and a pin 334 supported on the under surface of the bedplate 82.

The upper end of the pin 324 is provided with a hardened flat 338 and a hardened upper surface 338, both of which coact with a hardened plate 348 bolted to the under surface of the feed lever 84. The linkage system, pin and plate are so designed that when the solenoid 323 is inoperative the upper surface 338 of the pin is maintained by the spring 338 a few thousandths of an inch below the under surface of the plate 343, and thus does not affect the operation of the oscilthe web of the tape substantially parallel to the direction of feed of the strip from the point of attachment of the elements to a point substantially above said point of attachment, and sloping said parallel portion of the tape away from the point of attachment.

MAURICE VOITY.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS 

